Input: byd - enable absolute mode

The Windows driver's settings dialog contains a visualization of the
regions for the hardware edge scrolling capability, which uses a
temporarily-enabled limited-resolution absolute mode.

This patch enables this during normal operation, and combines the
absolute packets with the existing relative packets to provide
accurate absolute position and touch reporting.

It also adds documentation for all known gesture packets and
initialization commands.

Reviewed-by: Chris Diamand <chris@diamand.org>
Signed-off-by: Richard Pospesel <pospeselr@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

2 files changed, 369 insertions, 198 deletions

diff --git a/drivers/input/mouse/byd.c b/drivers/input/mouse/byd.c
index 9425e0f6c5ce..fdc243ca93ed 100644
--- a/drivers/input/mouse/byd.c
+++ b/drivers/input/mouse/byd.c
@@ -12,10 +12,12 @@
 #include <linux/input.h>
 #include <linux/libps2.h>
 #include <linux/serio.h>
+#include <linux/slab.h>
 
 #include "psmouse.h"
 #include "byd.h"
 
+/* PS2 Bits */
 #define PS2_Y_OVERFLOW  BIT_MASK(7)
 #define PS2_X_OVERFLOW  BIT_MASK(6)
 #define PS2_Y_SIGN      BIT_MASK(5)
@@ -26,69 +28,249 @@
 #define PS2_LEFT        BIT_MASK(0)
 
 /*
- * The touchpad reports gestures in the last byte of each packet. It can take
- * any of the following values:
+ * BYD pad constants
  */
 
-/* One-finger scrolling in one of the edge scroll zones. */
-#define BYD_SCROLLUP            0xCA
-#define BYD_SCROLLDOWN          0x36
-#define BYD_SCROLLLEFT          0xCB
-#define BYD_SCROLLRIGHT         0x35
-/* Two-finger scrolling. */
-#define BYD_2DOWN               0x2B
-#define BYD_2UP                 0xD5
-#define BYD_2LEFT               0xD6
-#define BYD_2RIGHT              0x2A
-/* Pinching in or out. */
-#define BYD_ZOOMOUT             0xD8
-#define BYD_ZOOMIN              0x28
-/* Three-finger swipe. */
-#define BYD_3UP                 0xD3
-#define BYD_3DOWN               0x2D
-#define BYD_3LEFT               0xD4
-#define BYD_3RIGHT              0x2C
-/* Four-finger swipe. */
-#define BYD_4UP                 0xCD
-#define BYD_4DOWN               0x33
+/*
+ * True device resolution is unknown, however experiments show the
+ * resolution is about 111 units/mm.
+ * Absolute coordinate packets are in the range 0-255 for both X and Y
+ * we pick ABS_X/ABS_Y dimensions which are multiples of 256 and in
+ * the right ballpark given the touchpad's physical dimensions and estimate
+ * resolution per spec sheet, device active area dimensions are
+ * 101.6 x 60.1 mm.
+ */
+#define BYD_PAD_WIDTH           11264
+#define BYD_PAD_HEIGHT          6656
+#define BYD_PAD_RESOLUTION      111
 
-int byd_detect(struct psmouse *psmouse, bool set_properties)
+/*
+ * Given the above dimensions, relative packets velocity is in multiples of
+ * 1 unit / 11 milliseconds.  We use this dt to estimate distance traveled
+ */
+#define BYD_DT                  11
+/* Time in jiffies used to timeout various touch events (64 ms) */
+#define BYD_TOUCH_TIMEOUT       msecs_to_jiffies(64)
+
+/* BYD commands reverse engineered from windows driver */
+
+/*
+ * Swipe gesture from off-pad to on-pad
+ *  0 : disable
+ *  1 : enable
+ */
+#define BYD_CMD_SET_OFFSCREEN_SWIPE             0x10cc
+/*
+ * Tap and drag delay time
+ *  0 : disable
+ *  1 - 8 : least to most delay
+ */
+#define BYD_CMD_SET_TAP_DRAG_DELAY_TIME         0x10cf
+/*
+ * Physical buttons function mapping
+ *  0 : enable
+ *  4 : normal
+ *  5 : left button custom command
+ *  6 : right button custom command
+ *  8 : disable
+ */
+#define BYD_CMD_SET_PHYSICAL_BUTTONS            0x10d0
+/*
+ * Absolute mode (1 byte X/Y resolution)
+ *  0 : disable
+ *  2 : enable
+ */
+#define BYD_CMD_SET_ABSOLUTE_MODE               0x10d1
+/*
+ * Two finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL           0x10d2
+/*
+ * Handedness
+ *  1 : right handed
+ *  2 : left handed
+ */
+#define BYD_CMD_SET_HANDEDNESS                  0x10d3
+/*
+ * Tap to click
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_TAP                         0x10d4
+/*
+ * Tap and drag
+ *  1 : tap and hold to drag
+ *  2 : tap and hold to drag + lock
+ *  3 : disable
+ */
+#define BYD_CMD_SET_TAP_DRAG                    0x10d5
+/*
+ * Touch sensitivity
+ *  1 - 7 : least to most sensitive
+ */
+#define BYD_CMD_SET_TOUCH_SENSITIVITY           0x10d6
+/*
+ * One finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL           0x10d7
+/*
+ * One finger scrolling function
+ *  1 : free scrolling
+ *  2 : edge motion
+ *  3 : free scrolling + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC      0x10d8
+/*
+ * Sliding speed
+ *  1 - 5 : slowest to fastest
+ */
+#define BYD_CMD_SET_SLIDING_SPEED               0x10da
+/*
+ * Edge motion
+ *  1 : disable
+ *  2 : enable when dragging
+ *  3 : enable when dragging and pointing
+ */
+#define BYD_CMD_SET_EDGE_MOTION                 0x10db
+/*
+ * Left edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_LEFT_EDGE_REGION            0x10dc
+/*
+ * Top edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_TOP_EDGE_REGION             0x10dd
+/*
+ * Disregard palm press as clicks
+ *  1 - 6 : smallest to largest
+ */
+#define BYD_CMD_SET_PALM_CHECK                  0x10de
+/*
+ * Right edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_RIGHT_EDGE_REGION           0x10df
+/*
+ * Bottom edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_BOTTOM_EDGE_REGION          0x10e1
+/*
+ * Multitouch gestures
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_MULTITOUCH                  0x10e3
+/*
+ * Edge motion speed
+ *  0 : control with finger pressure
+ *  1 - 9 : slowest to fastest
+ */
+#define BYD_CMD_SET_EDGE_MOTION_SPEED           0x10e4
+/*
+ * Two finger scolling function
+ *  0 : free scrolling
+ *  1 : free scrolling (with momentum)
+ *  2 : edge motion
+ *  3 : free scrolling (with momentum) + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC      0x10e5
+
+/*
+ * The touchpad generates a mixture of absolute and relative packets, indicated
+ * by the the last byte of each packet being set to one of the following:
+ */
+#define BYD_PACKET_ABSOLUTE                     0xf8
+#define BYD_PACKET_RELATIVE                     0x00
+/* Multitouch gesture packets */
+#define BYD_PACKET_PINCH_IN                     0xd8
+#define BYD_PACKET_PINCH_OUT                    0x28
+#define BYD_PACKET_ROTATE_CLOCKWISE             0x29
+#define BYD_PACKET_ROTATE_ANTICLOCKWISE         0xd7
+#define BYD_PACKET_TWO_FINGER_SCROLL_RIGHT      0x2a
+#define BYD_PACKET_TWO_FINGER_SCROLL_DOWN       0x2b
+#define BYD_PACKET_TWO_FINGER_SCROLL_UP         0xd5
+#define BYD_PACKET_TWO_FINGER_SCROLL_LEFT       0xd6
+#define BYD_PACKET_THREE_FINGER_SWIPE_RIGHT     0x2c
+#define BYD_PACKET_THREE_FINGER_SWIPE_DOWN      0x2d
+#define BYD_PACKET_THREE_FINGER_SWIPE_UP        0xd3
+#define BYD_PACKET_THREE_FINGER_SWIPE_LEFT      0xd4
+#define BYD_PACKET_FOUR_FINGER_DOWN             0x33
+#define BYD_PACKET_FOUR_FINGER_UP               0xcd
+#define BYD_PACKET_REGION_SCROLL_RIGHT          0x35
+#define BYD_PACKET_REGION_SCROLL_DOWN           0x36
+#define BYD_PACKET_REGION_SCROLL_UP             0xca
+#define BYD_PACKET_REGION_SCROLL_LEFT           0xcb
+#define BYD_PACKET_RIGHT_CORNER_CLICK           0xd2
+#define BYD_PACKET_LEFT_CORNER_CLICK            0x2e
+#define BYD_PACKET_LEFT_AND_RIGHT_CORNER_CLICK  0x2f
+#define BYD_PACKET_ONTO_PAD_SWIPE_RIGHT         0x37
+#define BYD_PACKET_ONTO_PAD_SWIPE_DOWN          0x30
+#define BYD_PACKET_ONTO_PAD_SWIPE_UP            0xd0
+#define BYD_PACKET_ONTO_PAD_SWIPE_LEFT          0xc9
+
+struct byd_data {
+        struct timer_list timer;
+        s32 abs_x;
+        s32 abs_y;
+        typeof(jiffies) last_touch_time;
+        bool btn_left;
+        bool btn_right;
+        bool touch;
+};
+
+static void byd_report_input(struct psmouse *psmouse)
 {
-        struct ps2dev *ps2dev = &psmouse->ps2dev;
-        unsigned char param[4];
+        struct byd_data *priv = psmouse->private;
+        struct input_dev *dev = psmouse->dev;
 
-        param[0] = 0x03;
-        param[1] = 0x00;
-        param[2] = 0x00;
-        param[3] = 0x00;
+        input_report_key(dev, BTN_TOUCH, priv->touch);
+        input_report_key(dev, BTN_TOOL_FINGER, priv->touch);
 
-        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-                return -1;
-        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-                return -1;
-        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-                return -1;
-        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-                return -1;
-        if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
-                return -1;
+        input_report_abs(dev, ABS_X, priv->abs_x);
+        input_report_abs(dev, ABS_Y, priv->abs_y);
+        input_report_key(dev, BTN_LEFT, priv->btn_left);
+        input_report_key(dev, BTN_RIGHT, priv->btn_right);
 
-        if (param[1] != 0x03 || param[2] != 0x64)
-                return -ENODEV;
+        input_sync(dev);
+}
 
-        psmouse_dbg(psmouse, "BYD touchpad detected\n");
+static void byd_clear_touch(unsigned long data)
+{
+        struct psmouse *psmouse = (struct psmouse *)data;
+        struct byd_data *priv = psmouse->private;
 
-        if (set_properties) {
-                psmouse->vendor = "BYD";
-                psmouse->name = "TouchPad";
-        }
+        serio_pause_rx(psmouse->ps2dev.serio);
+        priv->touch = false;
 
-        return 0;
+        byd_report_input(psmouse);
+
+        serio_continue_rx(psmouse->ps2dev.serio);
+
+        /*
+         * Move cursor back to center of pad when we lose touch - this
+         * specifically improves user experience when moving cursor with one
+         * finger, and pressing a button with another.
+         */
+        priv->abs_x = BYD_PAD_WIDTH / 2;
+        priv->abs_y = BYD_PAD_HEIGHT / 2;
 }
 
 static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
 {
-        struct input_dev *dev = psmouse->dev;
+        struct byd_data *priv = psmouse->private;
         u8 *pkt = psmouse->packet;
 
         if (psmouse->pktcnt > 0 && !(pkt[0] & PS2_ALWAYS_1)) {
@@ -102,53 +284,34 @@ static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
 
         /* Otherwise, a full packet has been received */
         switch (pkt[3]) {
-        case 0: {
+        case BYD_PACKET_ABSOLUTE:
+                /* Only use absolute packets for the start of movement. */
+                if (!priv->touch) {
+                        /* needed to detect tap */
+                        typeof(jiffies) tap_time =
+                                priv->last_touch_time + BYD_TOUCH_TIMEOUT;
+                        priv->touch = time_after(jiffies, tap_time);
+
+                        /* init abs position */
+                        priv->abs_x = pkt[1] * (BYD_PAD_WIDTH / 256);
+                        priv->abs_y = (255 - pkt[2]) * (BYD_PAD_HEIGHT / 256);
+                }
+                break;
+        case BYD_PACKET_RELATIVE: {
                 /* Standard packet */
                 /* Sign-extend if a sign bit is set. */
-                unsigned int signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
-                unsigned int signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
-                int dx = signx | (int) pkt[1];
-                int dy = signy | (int) pkt[2];
+                u32 signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
+                u32 signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
+                s32 dx = signx | (int) pkt[1];
+                s32 dy = signy | (int) pkt[2];
 
-                input_report_rel(psmouse->dev, REL_X, dx);
-                input_report_rel(psmouse->dev, REL_Y, -dy);
+                /* Update position based on velocity */
+                priv->abs_x += dx * BYD_DT;
+                priv->abs_y -= dy * BYD_DT;
 
-                input_report_key(psmouse->dev, BTN_LEFT, pkt[0] & PS2_LEFT);
-                input_report_key(psmouse->dev, BTN_RIGHT, pkt[0] & PS2_RIGHT);
-                input_report_key(psmouse->dev, BTN_MIDDLE, pkt[0] & PS2_MIDDLE);
+                priv->touch = true;
                 break;
         }
-
-        case BYD_SCROLLDOWN:
-        case BYD_2DOWN:
-                input_report_rel(dev, REL_WHEEL, -1);
-                break;
-
-        case BYD_SCROLLUP:
-        case BYD_2UP:
-                input_report_rel(dev, REL_WHEEL, 1);
-                break;
-
-        case BYD_SCROLLLEFT:
-        case BYD_2LEFT:
-                input_report_rel(dev, REL_HWHEEL, -1);
-                break;
-
-        case BYD_SCROLLRIGHT:
-        case BYD_2RIGHT:
-                input_report_rel(dev, REL_HWHEEL, 1);
-                break;
-
-        case BYD_ZOOMOUT:
-        case BYD_ZOOMIN:
-        case BYD_3UP:
-        case BYD_3DOWN:
-        case BYD_3LEFT:
-        case BYD_3RIGHT:
-        case BYD_4UP:
-        case BYD_4DOWN:
-                break;
-
         default:
                 psmouse_warn(psmouse,
                              "Unrecognized Z: pkt = %02x %02x %02x %02x\n",
@@ -157,134 +320,76 @@ static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
                 return PSMOUSE_BAD_DATA;
         }
 
-        input_sync(dev);
+        priv->btn_left = pkt[0] & PS2_LEFT;
+        priv->btn_right = pkt[0] & PS2_RIGHT;
 
-        return PSMOUSE_FULL_PACKET;
-}
+        byd_report_input(psmouse);
 
-/* Send a sequence of bytes, where each is ACKed before the next is sent. */
-static int byd_send_sequence(struct psmouse *psmouse, const u8 *seq, size_t len)
-{
-        unsigned int i;
-
-        for (i = 0; i < len; ++i) {
-                if (ps2_command(&psmouse->ps2dev, NULL, seq[i]))
-                        return -1;
+        /* Reset time since last touch. */
+        if (priv->touch) {
+                priv->last_touch_time = jiffies;
+                mod_timer(&priv->timer, jiffies + BYD_TOUCH_TIMEOUT);
         }
-        return 0;
-}
-
-/* Keep scrolling after fingers are removed. */
-#define SCROLL_INERTIAL         0x01
-#define SCROLL_NO_INERTIAL      0x02
-
-/* Clicking can be done by tapping or pressing. */
-#define CLICK_BOTH              0x01
-/* Clicking can only be done by pressing. */
-#define CLICK_PRESS_ONLY        0x02
 
-static int byd_enable(struct psmouse *psmouse)
-{
-        const u8 seq1[] = { 0xE2, 0x00, 0xE0, 0x02, 0xE0 };
-        const u8 seq2[] = {
-                0xD3, 0x01,
-                0xD0, 0x00,
-                0xD0, 0x04,
-                /* Whether clicking is done by tapping or pressing. */
-                0xD4, CLICK_PRESS_ONLY,
-                0xD5, 0x01,
-                0xD7, 0x03,
-                /* Vertical and horizontal one-finger scroll zone inertia. */
-                0xD8, SCROLL_INERTIAL,
-                0xDA, 0x05,
-                0xDB, 0x02,
-                0xE4, 0x05,
-                0xD6, 0x01,
-                0xDE, 0x04,
-                0xE3, 0x01,
-                0xCF, 0x00,
-                0xD2, 0x03,
-                /* Vertical and horizontal two-finger scrolling inertia. */
-                0xE5, SCROLL_INERTIAL,
-                0xD9, 0x02,
-                0xD9, 0x07,
-                0xDC, 0x03,
-                0xDD, 0x03,
-                0xDF, 0x03,
-                0xE1, 0x03,
-                0xD1, 0x00,
-                0xCE, 0x00,
-                0xCC, 0x00,
-                0xE0, 0x00,
-                0xE2, 0x01
-        };
-        u8 param[4];
-
-        if (byd_send_sequence(psmouse, seq1, ARRAY_SIZE(seq1)))
-                return -1;
-
-        /* Send a 0x01 command, which should return 4 bytes. */
-        if (ps2_command(&psmouse->ps2dev, param, 0x0401))
-                return -1;
-
-        if (byd_send_sequence(psmouse, seq2, ARRAY_SIZE(seq2)))
-                return -1;
-
-        return 0;
+        return PSMOUSE_FULL_PACKET;
 }
 
-/*
- * Send the set of PS/2 commands required to make it identify as an
- * intellimouse with 4-byte instead of 3-byte packets.
- */
-static int byd_send_intellimouse_sequence(struct psmouse *psmouse)
+static int byd_reset_touchpad(struct psmouse *psmouse)
 {
         struct ps2dev *ps2dev = &psmouse->ps2dev;
         u8 param[4];
-        int i;
+        size_t i;
+
         const struct {
                 u16 command;
                 u8 arg;
         } seq[] = {
-                { PSMOUSE_CMD_RESET_BAT, 0 },
-                { PSMOUSE_CMD_RESET_BAT, 0 },
-                { PSMOUSE_CMD_GETID, 0 },
-                { PSMOUSE_CMD_SETSCALE11, 0 },
-                { PSMOUSE_CMD_SETSCALE11, 0 },
-                { PSMOUSE_CMD_SETSCALE11, 0 },
-                { PSMOUSE_CMD_GETINFO, 0 },
-                { PSMOUSE_CMD_SETRES, 0x03 },
+                /*
+                 * Intellimouse initialization sequence, to get 4-byte instead
+                 * of 3-byte packets.
+                 */
                 { PSMOUSE_CMD_SETRATE, 0xC8 },
                 { PSMOUSE_CMD_SETRATE, 0x64 },
                 { PSMOUSE_CMD_SETRATE, 0x50 },
                 { PSMOUSE_CMD_GETID, 0 },
-                { PSMOUSE_CMD_SETRATE, 0xC8 },
-                { PSMOUSE_CMD_SETRATE, 0xC8 },
-                { PSMOUSE_CMD_SETRATE, 0x50 },
-                { PSMOUSE_CMD_GETID, 0 },
-                { PSMOUSE_CMD_SETRATE, 0x64 },
-                { PSMOUSE_CMD_SETRES, 0x03 },
-                { PSMOUSE_CMD_ENABLE, 0 }
+                { PSMOUSE_CMD_ENABLE, 0 },
+                /*
+                 * BYD-specific initialization, which enables absolute mode and
+                 * (if desired), the touchpad's built-in gesture detection.
+                 */
+                { 0x10E2, 0x00 },
+                { 0x10E0, 0x02 },
+                /* The touchpad should reply with 4 seemingly-random bytes */
+                { 0x14E0, 0x01 },
+                /* Pairs of parameters and values. */
+                { BYD_CMD_SET_HANDEDNESS, 0x01 },
+                { BYD_CMD_SET_PHYSICAL_BUTTONS, 0x04 },
+                { BYD_CMD_SET_TAP, 0x02 },
+                { BYD_CMD_SET_ONE_FINGER_SCROLL, 0x04 },
+                { BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC, 0x04 },
+                { BYD_CMD_SET_EDGE_MOTION, 0x01 },
+                { BYD_CMD_SET_PALM_CHECK, 0x00 },
+                { BYD_CMD_SET_MULTITOUCH, 0x02 },
+                { BYD_CMD_SET_TWO_FINGER_SCROLL, 0x04 },
+                { BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC, 0x04 },
+                { BYD_CMD_SET_LEFT_EDGE_REGION, 0x00 },
+                { BYD_CMD_SET_TOP_EDGE_REGION, 0x00 },
+                { BYD_CMD_SET_RIGHT_EDGE_REGION, 0x00 },
+                { BYD_CMD_SET_BOTTOM_EDGE_REGION, 0x00 },
+                { BYD_CMD_SET_ABSOLUTE_MODE, 0x02 },
+                /* Finalize initialization. */
+                { 0x10E0, 0x00 },
+                { 0x10E2, 0x01 },
         };
 
-        memset(param, 0, sizeof(param));
         for (i = 0; i < ARRAY_SIZE(seq); ++i) {
+                memset(param, 0, sizeof(param));
                 param[0] = seq[i].arg;
                 if (ps2_command(ps2dev, param, seq[i].command))
-                        return -1;
+                        return -EIO;
         }
 
-        return 0;
-}
-
-static int byd_reset_touchpad(struct psmouse *psmouse)
-{
-        if (byd_send_intellimouse_sequence(psmouse))
-                return -EIO;
-
-        if (byd_enable(psmouse))
-                return -EIO;
-
+        psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
         return 0;
 }
 
@@ -314,9 +419,50 @@ static int byd_reconnect(struct psmouse *psmouse)
         return 0;
 }
 
+static void byd_disconnect(struct psmouse *psmouse)
+{
+        struct byd_data *priv = psmouse->private;
+
+        if (priv) {
+                del_timer(&priv->timer);
+                kfree(psmouse->private);
+                psmouse->private = NULL;
+        }
+}
+
+int byd_detect(struct psmouse *psmouse, bool set_properties)
+{
+        struct ps2dev *ps2dev = &psmouse->ps2dev;
+        u8 param[4] = {0x03, 0x00, 0x00, 0x00};
+
+        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+                return -1;
+        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+                return -1;
+        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+                return -1;
+        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+                return -1;
+        if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
+                return -1;
+
+        if (param[1] != 0x03 || param[2] != 0x64)
+                return -ENODEV;
+
+        psmouse_dbg(psmouse, "BYD touchpad detected\n");
+
+        if (set_properties) {
+                psmouse->vendor = "BYD";
+                psmouse->name = "TouchPad";
+        }
+
+        return 0;
+}
+
 int byd_init(struct psmouse *psmouse)
 {
         struct input_dev *dev = psmouse->dev;
+        struct byd_data *priv;
 
         if (psmouse_reset(psmouse))
                 return -EIO;
@@ -324,14 +470,39 @@ int byd_init(struct psmouse *psmouse)
         if (byd_reset_touchpad(psmouse))
                 return -EIO;
 
+        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+
+        memset(priv, 0, sizeof(*priv));
+        setup_timer(&priv->timer, byd_clear_touch, (unsigned long) psmouse);
+
+        psmouse->private = priv;
+        psmouse->disconnect = byd_disconnect;
         psmouse->reconnect = byd_reconnect;
         psmouse->protocol_handler = byd_process_byte;
         psmouse->pktsize = 4;
         psmouse->resync_time = 0;
 
-        __set_bit(BTN_MIDDLE, dev->keybit);
-        __set_bit(REL_WHEEL, dev->relbit);
-        __set_bit(REL_HWHEEL, dev->relbit);
+        __set_bit(INPUT_PROP_POINTER, dev->propbit);
+        /* Touchpad */
+        __set_bit(BTN_TOUCH, dev->keybit);
+        __set_bit(BTN_TOOL_FINGER, dev->keybit);
+        /* Buttons */
+        __set_bit(BTN_LEFT, dev->keybit);
+        __set_bit(BTN_RIGHT, dev->keybit);
+        __clear_bit(BTN_MIDDLE, dev->keybit);
+
+        /* Absolute position */
+        __set_bit(EV_ABS, dev->evbit);
+        input_set_abs_params(dev, ABS_X, 0, BYD_PAD_WIDTH, 0, 0);
+        input_set_abs_params(dev, ABS_Y, 0, BYD_PAD_HEIGHT, 0, 0);
+        input_abs_set_res(dev, ABS_X, BYD_PAD_RESOLUTION);
+        input_abs_set_res(dev, ABS_Y, BYD_PAD_RESOLUTION);
+        /* No relative support */
+        __clear_bit(EV_REL, dev->evbit);
+        __clear_bit(REL_X, dev->relbit);
+        __clear_bit(REL_Y, dev->relbit);
 
         return 0;
 }
diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index 39d1becd35c9..5784e20542a4 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -846,7 +846,7 @@ static const struct psmouse_protocol psmouse_protocols[] = {
 #ifdef CONFIG_MOUSE_PS2_BYD
         {
                 .type           = PSMOUSE_BYD,
-                .name           = "BydPS/2",
+                .name           = "BYDPS/2",
                 .alias          = "byd",
                 .detect         = byd_detect,
                 .init           = byd_init,